The present invention relates to a method for preparing a snack in which chlorophyll-containing plants are employed as ingredients and more specifically to a method for preparing a snack which makes it possible to effectively prevent discoloration of the snack and deterioration of the taste thereof during storage.
There have conventionally been proposed a variety of methods for preparing snack confectioneries in which chlorophyll-containing plants are employed as ingredients. For instance, Japanese Unexamined Patent Publication (hereinafter referred to as "J. P. KOKAI") No. Sho 61-58539 (corresponding to U.S. Pat. No. 4,748,037) discloses a method which comprises supplying beans, which may be entire grains or whose husk has been removed, to a twin-screw extruder, adjusting the water content thereof with or without addition of water, then subjecting the ingredient to extrusion-cooking, spraying an aqueous salt solution on the extruded product and then drying by passing air therethrough and J. P. KOKAI No. Sho 61-9253 discloses a method which comprises primarily puffing a starch-containing substance in an extruder, pulverizing the primarily puffed substance, mixing heat-sensitive components with the pulverized substance and then extruding the mixture through a die at a low temperature to thus carry out puffing.
However, such snack confectioneries prepared from plants which contain chlorophyll suffer from problems of, for instance, discoloration of the confectioneries and deterioration of the taste thereof (more specifically, the taste peculiar to the plants is reduced while a different taste is given out) during the storage. These problems are conspicuous, in particularly when the chlorophyll-containing plant is the pea or when the snack confectioneries of this kind are prepared through a puffing treatment.